Hitech is one of the companies that can provide 4 layer multi-layer pcb, such as 1200mm, 1500mm and 1750mm long pcb board. If you are looking for a 4-layer long pcb, it is important to source them from a reliable manufacturer who understands your requirements effectively. Hitech is one of the leading manufacturers of 4 layers pcb in China. https://hitechcircuits.com/
If you have the requirement for long PCB, please feel free to contact sales3@hitechpcb.com